I've recently dinged 40/40 on my Warrior Priest and thought that I would share some of those little of quality of life annoyances that I've run into. These aren't "class redesign" type of issues but more like a hair in your soup or a puddle that you have to step through every day during your commute.

Salvation
Annoyance: Despite your aura being a passive buff, you need to recast it every time you gain/lose bolster. This can get really annoying with RvR town rezzes or questing in an RvR zone.

Solution: Self-buffs are removed and then reapplied with the new stats when gaining or losing bolster. Buffs from other players are still lost as usual.

Annoyance: There are a bunch of skills and tactics in this game that generate Action Points, but Salv WPs more or less ignore AP and are extremely limited by available RF.

Solution: Any AP regen applied to a Salvation WP instead generates RF. To prevent this change from overpowering the class RF could be generated with a coefficient e.g. regenning 15 RF instead of 60 AP.

Grace:

Annoyance: Each non-aura buff is a separate attack, and each buff has a short duration. So a decent portion of your time and GCDs is spent on boring buff maintenance instead of smashing faces to heal other faces. And the constant retargeting for buffs can screw up heals.

Annoyance: Getting optimal block on your shield is YET ANOTHER short term buff to maintain. Why???

Solution: Add the block value to Grace shields. Or a tactic. Or one of the other buff skills. Basically, remove the discrete single-purpose buff. To add insult to injury, when you miss with this or other buffs you're left buffless. Yuck!

Wrath:

Annoyance: Lack of pure damage RF dump. Sure, Divine Assault or Sacrifice let you heal a piddly amount, but Wrath needs a good damage spender to really feel like a DPS spec.

Solution: Add a spender to wrath that consumes RF. Something with a nice walliop.

Annoyance: The guilty soul buff only triggers when using wrath skills. This means that you're not proccing guilty soul on your buff attack skills. Or your Divine Assault. Or your silence. Or your purge. Even with decent crit I've found it really tough to keep stacks of this skill up, depending on the cadence of skills.

Solution: Allow Guilty Soul to proc from all melee skill crits. If this is deemed overpowered decrease the amount of benefit per stack and increase the total number of stacks.